Web-Spinning Goats
Overview Scientists have genetically engineered goats to yield a spider’s web protein, which have numerous applications. Spider silk is acknowledged as a natural material that is 6 times stronger than steel of the same weight (2). This product is harvested within the goat’s milk by isolating the proteins which are spun into purified thread-like fibers (4). Scientists genetically modified goats to spin spider silk in hope to massively produce more silk than with silk spinning spiders (1). Spider farms have been attempted, but these arachnid farms usually conclude in the spiders killing each other due to territorial behaviors; thus introducing the idea of utilizing goats (1). Through the work from Nexia Bio technologies and with the help from the National Science Foundation, a scientist named Lewis, with his team, generated a web-spinning goat (1). How is This Done? Researcher’s genetically modified this goat by inserting a copied drag line silk gene from a Golden orb-weaver spider into the DNA of a goat’s embryo with tiny metal inserters (2, 4). The gene thus gets taken up into DNA, with the success rate of 5%, through DNA recombination (2,4). This then creates the goat to be 1/70,000 part spider (2). After the egg is transplanted back into the mother, a baby goat with this spider silk gene is born (4).Lewis and his team do blood tests on the baby goats to conclude which ones successfully obtain the silk spinning gene (1). This gene will only produce silk, which commercially is known as biosteel, when the goat is lactating/being milked (2). After the goat is milked for the protein, it is taken back into the lab where it is isolated and yields out a thick syrupy substance called spindo through a lab technique called chromatography (2, 3). This substance is very similar in structure to actual silk from the glands of a spider (2). To mimic spinnerets, like in spiders to eject the silk from, scientists eject the spindo from small holes in stainless steel to create thread-like silk (2). By introducing the proteins to oxygen, they line up and snap together, creating a strong fiber (2). Within Lewis’ work there have been no differences in health of normal goats versus transgenic goats (1). Biosteel This a trademark name for the fiber material produced by the transgenic goats (3). It is known to be 7-10 times as strong as steel and can stretch up to 20 times its size without losing its strength properties (3). Biosteel is also to be known to have high resistance to extreme temperatures without losing its properties between the ranges of -20 to 330 degrees Celsius (3). With the special properties this provides many benefits for medical and commercial products Benefits Spider silk has been benefiting people since before the Middle Ages with its healing abilities (2). An upmost beneficial advantage this material has to offer is through its medical purposes. Most recently researchers and doctors have been trying to use spider silk in nerve ligament and joint replacements (2). There has also been research done on jaw repair for veterans returning home from Iraq and Afghanistan (1). This material is beneficial especially to jaw repair because this material is strong enough to allow usage of the jaw to allow it to heal as well as it providing a thinner material versus current materials being too thick to work with (1). Another benefit it has to offer is that it can repair tendons as well as nerves (2). Doctors state that spider silk is ideal for surgical purposes since it has high teat resistance, tensile strength and a smooth surface (2). It also is biodegradable which when inserted into the human body; it diminishes the chance of inflammation (2). The spider silk can also be beneficial for commercial products. It has been used to develop bulletproof vests, along with fishing line and surgical thread (2). This can also lead to much safer suspension bridges, rope, rust-free paneling and bandages (2, 4). The handling of goats rather than arachnid farms or silk spinning worm farms is shown to be more beneficial and have a higher success for demand of silk (2). With the silk spinning goat farms they are able to harvest enough to satisfy demands (2). Around 4 drops of genetically modified goat’s milk produces around 4 meters of silk (2). Limitations Just like every other genetically modified animals or plants, there are some sorts of limitations. Since the spider web is produced by goats it only has 30% of the strength of natural spider silk (2). This could affect how the product is utilized. Another limitation that surfaced with the creation of the transgenic goat is further analysis of the goats (2). Lewis has stated that there seems to be no physical or mental differences between the transgenic or regular goats, but further research has to be conducted to fully claim that that is true (2). Further Work It is in hope one day that scientists are able to produce more quantities of this product through plants. Right now scientists are looking to genetically modify the alfalfa plant to produce this silk (1). They had chosen the alfalfa plant due to accessible and easy transportation across the country, as well as the high protein content the plant naturally produces (1). This creates the plant to be the ideal crop for this genetic modification. The plant can also be used to make ethanol once extracting the silk protein (1). Video Link http://www.nsf.gov/news/special_reports/science_nation/spidersilk.jsp Resources 1. O'Brien, M and Walton, M. Got Silk? National Science Foundation. May 3 2010. http://www.nsf.gov/news/special_reports/science_nation/spidersilk.jsp 2. Web Spinning Goats. GMO. 2013. http://gmo-web-spinning-goat.weebly.com/web-spinning-goat.html 3. Biosteel. Wikipedia. http://en.wikipedia.org/wiki/BioSteel 4. Kuo, Katherine. Web-Spinning Goats. Prezi. March 16 2013. http://prezi.com/mor8ol_zpkql/web-spinning-goats/